Bad Overall Service and Failed Promises

I ordered a SIM card on 29th August 2019. I paid for it online and was guaranteed 5 working days delivery. I haven’t received my sim. I called rain and rearranged delivery to my work address as I won’t be able to take off again to wait for the sim to come. They assured me it would be delivered and yet I still don’t have something that I already paid for. I have not received any communication back about my complaint I made or a refund for me purchase. I’m very disappointed.